I found this really interesting too from the NIWA's press release from Feb 2018:

Quote:

Overview

February 2018 was marked by two ex-Tropical Cyclones, Fehi and Gita, that impacted New Zealand on the 1st and 20th of the month, respectively. These two storms contributed to lower than normal sea level pressure that extended from the tropics to the north of New Zealand and southward across the country. The North Island had more northeast winds than normal, consistent with ongoing La Niña conditions, while the South Island observed only weak air flow anomalies. Sea surface temperatures (SSTs) in New Zealand coastal waters and across the Tasman Sea remained well above average during the month.

And March:

Quote:

OverviewMarch 2018 was characterised by significantly higher pressure than normal to the east of New Zealand. This pressure pattern, in concert with the decaying La Niña in the tropical Pacific, caused more northeasterly winds than usual over the country. These warm, humid air masses, combined with the remnants of the marine heatwave in the Tasman Sea, influenced higher than usual temperatures over New Zealand as well as some heavy rainfall events.

March was a warm month across New Zealand, with well above average (>1.20°C of average) or above average (0.51 to 1.20°C of average) mean temperatures experienced almost everywhere across the country. Only isolated parts of Tasman and Southland experienced near average temperatures (-0.50 to 0.50°C). As was observed in February, the number of record and near-record high mean minimum (night time) temperatures in March exceeded the number of record and near-record high mean maximum (day time) temperatures, due to the combination of the marine heat wave along with warm and humid northeasterlies, thereby keeping overnight temperatures elevated.

The nationwide average temperature in March 2018 was 16.9°C (1.3°C above the 1981-2010 March average from NIWA’s seven station temperature series which begins in 1909). March 2018 was the sixth-warmest March in the seven-station series. So far, 2018 has had the warmest start to the calendar year on record, with mean temperatures 1.75°C above the 1981-2010 average for January to March combined. The previous record was held by 1998, with January-March mean temperatures that were 1.51°C above average..

March rainfall was spatially patchy across New Zealand, with heavy rain leading to flooding in some areas. Well above normal rainfall totals (>149% of normal) were experienced in the central North Island, the eastern North Island south of Napier, Kapiti Coast, Nelson, south Canterbury, north and central Otago, and Fiordland. Rainfall was above normal (120-149% of normal) in Northland, the southern half of the North Island, and Tasman. Below normal rainfall (50-79%) was experienced in isolated patches of Auckland, Waikato, Bay of Plenty, East Cape, Christchurch, Dunedin, and Southland. Near normal rainfall (80-119% of normal) was observed elsewhere.

By the end of March, soil moisture levels were much above normal for the time of year across most of New Zealand. Soils were drier than normal for East Cape, parts of Manawatu-Whanganui, eastern Southland, and Stewart Island.

The marine heatwave stole our moisture and pumped it down through the Tasman Sea and NZ imho. That is my theory anyway. La-Nina probably not to blame...the Pacific was no doubt in La-Nina mode at the time but its effects were imo blocked and couldn't reach us here.

It’s looking very interesting and it seems we’re about to be thrown another curve-ball. ENSO is stuffed.

That would be due to that incursion of subsurface cooling from the south. Same as last year. Unless of course you belief the tooth fairy dragged a cold anomaly out of a huge warm body of water moving east along the thermocline the past few months.

Its called an upwelling Kelvin wave, and the charts I posted previously show it quite clearly happening. No fairies required, just an understanding of wave physics.

The water to the south is warmer. The cold subsurface anomalies are clearly due upwelling of colder water from below.

Mike, what would be the cause of this upwelling?

Coriolos force - when high pressure tries to push air around coriolos force deflects the wind at a strong angle. When the wind tries to push ocean water around, coriolos also deflects the water. Easterly winds push water from east to west in the far west. The coriolos deflection causes the surface waters to be deflected towards the north in the NH, and towards the south in the SH. This creates a gap and colder water from below needs to push up to replace this water.

The water to the south is warmer. The cold subsurface anomalies are clearly due upwelling of colder water from below.

Mike, what would be the cause of this upwelling?

Coriolos force - when high pressure tries to push air around coriolos force deflects the wind at a strong angle. When the wind tries to push ocean water around, coriolos also deflects the water. Easterly winds push water from east to west in the far west. The coriolos deflection causes the surface waters to be deflected towards the north in the NH, and towards the south in the SH. This creates a gap and colder water from below needs to push up to replace this water.

News to NASA....they reckon it’s as a result of winds blowing across the surface of a body of water.

Quote:

The Coriolis Effect can be seen in action in the general circulation of the atmosphere. The winds at all latitudes to the north of 0° deflect to the right of their intended path in the Northern Hemisphere. The Coriolis Effect does not impact the wind speed, only the wind direction.

Therefore the cause of stronger upwelling seen off the coast of South America has nothing to do with the coriolis effect and is a direct result of ENSO ergo what Petros was cleverly alluding to.

Discovered that's a recycled video from August 2013 in the far southern Brazilian city of Caxias do Sul on the Serra Gaucha highlands. Check out the comments/replies mentioning this (Chrome makes it easy with the translate function): https://www.youtube.com/watch?v=rBXuoKZN-nsLooking at the article posted in those comments, on this occasion snow did fall but only looks like flurries. There were also freezing rain/fog reports. (The cities mentioned: Gramado, Caxias do Sul, Bom Jesus, Sao Francisco)

..might pay though to put something like contribution of coriolis effect to upwelling into a google search...

No-one said there wasn't a contribution, rather that it isn't two dimensional and I have spent the past several years reading about coriolis and ocean waves but thanks for making me aware of this new phenomena known as google. That two dimensional thinking set one individual on the wrong path when pushing a warming trend last year. Upwelling occurs in different sections of oceanic currents at different times of the year and the temperature of those currents is not consistent and nor to coriolis generated currents simply move east to west.

Cold anomalies extend down to a depth of 400 mtrs off the Sth American coast and are still impacting the equatorial pacific.

Meanwhile, there is clearly little respect for Mick's request to omit AGW discussion and the same blinded warming fanaticism , limited to the parroting of wildly fluctuating and hyper-reactive model runs has dominated the thread for the best part of 18 months. Whilst it is true that models certainly have their place, only a fool would put all their faith in them.

This is where I go back to lurking .

_________________________ "When it comes to the weather, "occasionally" is better than "not at all".

Discovered that's a recycled video from August 2013 in the far southern Brazilian city of Caxias do Sul on the Serra Gaucha highlands. Check out the comments/replies mentioning this (Chrome makes it easy with the translate function): https://www.youtube.com/watch?v=rBXuoKZN-nsLooking at the article posted in those comments, on this occasion snow did fall but only looks like flurries. There were also freezing rain/fog reports. (The cities mentioned: Gramado, Caxias do Sul, Bom Jesus, Sao Francisco)

What I'm finding curious at the moment are the negative sea level anomalies just to the North of the equator (at 10N) and not to the South.

_________________________
This post and any other post by Locke is NOT an official forecast & should not be used as such. It's just my opinion & may or may not be backed by sound meteorological data. For official information, refer to Australian Bureau of Meteorology products.